A file server is a type of storage server that operates on behalf of one or more clients to store and manage shared files in a set of mass storage devices, such as magnetic or optical storage based disks. The mass storage devices are typically organized as one or more groups of Redundant Array of Independent (or Inexpensive) Disks (RAID). One configuration in which file servers can be used is a network attached storage (NAS) configuration. In a NAS configuration, a file server can be implemented in the form of an appliance that attaches to a network, such as a local area network (LAN) or a corporate intranet. Examples of such an appliance include any of the NetApp Filer® products made by Network Appliance, Inc. in Sunnyvale, Calif., or the SpinServer® products formerly made by Spinnaker Networks, Inc., which was acquired by Network Appliance.
File servers usually use storage-optimized protocols to move data between the file server and the storage medium. One such protocol in the Fibre Channel specification network coupled with a small computer system interface (SCSI) protocol stack. File servers are also connected to traffic networks via some traffic protocol, such as Ethernet and transmission control protocol/Internet protocol (TCP/IP) stack. Traditionally, the file server thus included two network adapters to be able to connect to two separate networks: a storage network and a traffic network (e.g., a Fibre Channel network and an Ethernet network). Alternatively, the file server included a dual-port network adapter, where each port is associated with a protocol and a separate transmit and receive chain, in effect being two network adapters on a single card.
This two-network two-adapter setup has various disadvantages, including the expense associated with building and maintaining two redundant networks and using two network adapters in each device connected to the two networks. Therefore it would be advantageous to have a multi-protocol network adapter that can receive data over a single network regardless of protocol.